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771.
High and low molecular weight kininogens (HK and LK) modulate inflammatory responses, serve as precursors of kinins, inhibit cysteine proteinases, and modulate thrombin activation of platelets. Differential splicing yields two different mRNAs for HK and LK. We report the first molecular characterization of a kininogen gene mutation in a patient lacking LK and HK. No gross DNA deletion or insertion was detected by Southern blots, and LK and HK mRNAs were normal size on Northern blots. Exon sequences amplified by polymerase chain reaction showed a C-->T transition at nucleotide 587, resulting in a CGA (Arg)--> TGA (Stop) mutation in exon 5 before the splice site in exon 10, thus preventing synthesis of both HK and LK. The mutation eliminated the recognition site of the restriction enzyme Csp45I. Results of Csp45I digestion of the polymerase chain reaction-amplified exon 5 DNA fragment of the patient (lacking kininogens), three daughters (approximately 50% HK), and 1 granddaughter (normal HK) revealed that the patient was homozygous, while the three daughters were heterozygous, and the granddaughter was normal. We conclude that a single base mutation in the kininogen gene exon 5 was responsible for kininogen deficiency in the Williams family.  相似文献   
772.
Uniformly 14C-ring-labelled tert-butylhydroquinone (TBHQ) was diluted with non-radioactive TBHQ and administered orally (for excretion studies) to Fischer 344 rats. An average of 72.9% and 10.6% of the administered radioactivity was recovered in the urine and faeces, respectively, of male rats, and 77.3% and 8.2% in the urine and faeces, respectively, of female rats in 4 days. No significant sex-related differences were found in either excretion, tissue distribution or urinary metabolites of TBHQ-derived radiolabel. For distribution studies, intraperitoneal doses were administered to female rats, and tissue levels of radiolabel were determined at various times after dosing. The parent compound quickly disappeared from tissue in vivo. The highest concentrations of radiolabel were found in the liver and kidneys. The urinary metabolites consisted of conjugated TBHQ and unidentified polar substance(s).  相似文献   
773.
Using ethylene glycol (EG) and vitamin D3 as crystal-inducing diet (CID) in rats, we investigated the effect of the dosage of EG on the generation of chronic calcium oxalate (CaOx) nephrolithiasis. We collected weekly 24 hour urines and measured herein the amount of oxalate, calcium, glycosaminoglycans (GAG's), creatinine, protein, alkaline phosphatase (AP), gamma-glutamyl transpeptidase (gamma-GT), and N-acetyl-beta-glucosaminidase (NAG). The potential of these urines to inhibit crystal growth and agglomeration was also evaluated. After four weeks, the kidneys were screened by histology and radiography for the presence of CaOx crystals and the amount of kidney-associated oxalate was biochemically measured. Using 0.5 vol.% EG, only a part of the rats showed CaOx deposition in the renal cortex and/or medulla, without obvious differences between Wistar and Sprague-Dawley (SD) rats. If a dietary EG concentration of 0.75, 1.0, or 1.5 vol.% was used, the amount of kidney-associated oxalate was proportionally higher and CaOx crystal formation was consistently found in all rats. Most crystals were encountered in the cortex, whereas in the medulla and the papillary region, crystals were only occasionally detected. From these data, we conclude that in the chronic rat model, based on EG and vitamin D3, a consistent deposition of CaOx crystals is obtained using a EG concentration of at least 0.75%.  相似文献   
774.
775.
The authors compare the strategus needed for the elimination of paraplegia and for protection of abdominal organs after replacement of descending thoracic or thoraco-abdominal aorta. They analyse single technique considering the advantages and the controindications; furthermore they compare these properties and those of possible variants in the light of the presentation; type of disease and general conditions of the patient. These considerations are in agreement with later literature as well as the attitude of the surgeon.  相似文献   
776.
BACKGROUND: For patients with invasive bladder cancer the usual recommended treatment is radical cystectomy, although transurethral resection of the tumor, systemic chemotherapy, and radiotherapy are each effective in some patients. We sought to determine whether these treatments in combination might be as effective as radical cystectomy and thus might allow the bladder to be preserved and the cancer cured. METHODS: We enrolled 53 consecutive patients with muscle-invading bladder cancer (stages T2 through T4, NXM0) in a trial of transurethral surgery, combination chemotherapy, and irradiation (4000 cGy) with concurrent cisplatin administration. Urologic evaluation of the tumor response directed further therapy: radical cystectomy in the 8 patients who had incomplete responses, additional chemotherapy and radiotherapy (6480 cGy) in the 34 patients who had complete responses or who were unsuited for cystectomy, and alternative care in the 11 patients who could not tolerate either irradiation or chemotherapy. RESULTS: After a median follow-up of 48 months, 24 of the 53 patients (45 percent) were alive and free of detectable tumor. In 31 patients (58 percent) the bladder was free of invasive tumor and functioning well, even though in 9 (17 percent) a superficial tumor recurred and required further transurethral surgery and intravesical drug therapy. Of the 28 patients who had complete responses after initial treatment, 89 percent had functioning tumor-free bladders. CONCLUSIONS: Conservative combination treatment may be an acceptable alternative to immediate cystectomy in selected patients with bladder cancer, although a randomized clinical trial that included a group for simultaneous comparison would be required to produce definitive results.  相似文献   
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779.
A 23-year-old woman presented with low back pain of several months' duration. A tuberculous infection of the left sacroiliac joint was diagnosed by closed-needle biopsy. The clinical presentation, radiological features and outcome of this patient are discussed.  相似文献   
780.
Six human colorectal tumour cell lines with various degrees of differentiation were studied. Each of the cell lines studied showed an in vitro platelet proaggregating activity, represented by the induction of typical aggregation waves. This activity was dose-dependent and probably related to a thrombin-dependent mechanism. However, the degree of cell differentiation did not correlate with the proaggregating activity. In fact, significant differences were observed between the two well differentiated cell lines, while a comparison between well and poorly differentiated cell lines did not reveal any difference. These results were confirmed by the ultrastructural observations, indicating that similar platelet-tumour cell interaction may be found in all the cell lines studied. The present results suggest that platelet proaggregating activity of the human colorectal tumour cell lines under investigation is unrelated to their degree of differentiation.  相似文献   
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